Immunogenicity and Safety of a Measles-Mumps-Rubella Vaccine Administered as a First Dose to Children Aged 12 to 15 Months: A Phase III, Randomized, Noninferiority, Lot-to-Lot Consistency Study

J Pediatric Infect Dis Soc. 2020 Apr 30;9(2):194-201. doi: 10.1093/jpids/piz010.


Background: MMR II (M-M-R II [Merck & Co, Inc.]) is currently the only measles, mumps, and rubella (MMR) vaccine licensed in the United States. A second MMR vaccine would mitigate the potential risk of vaccine supply shortage or delay. In this study, we assessed the immunogenicity and safety of another MMR vaccine (MMR-RIT [Priorix, GlaxoSmithKline]) compared with those of the MMR II in 12- to 15-month-old children who received it as a first dose.

Methods: In this phase III, observer-blinded, noninferiority, lot-to-lot consistency clinical trial ( identifier NCT01702428), 5003 healthy children were randomly assigned to receive 1 dose of MMR-RIT (1 of 3 production lots) or MMR II along with other age-recommended routine vaccines. We evaluated the immunogenicity of all vaccines in terms of antibody concentrations (by using an enzyme-linked immunosorbent assay or electrochemiluminescence assay) and/or seroresponse rates 43 days after vaccination. We also assessed the reactogenicity and safety of the vaccines.

Results: Immunoresponses after vaccination with MMR-RIT were robust and noninferior to those after vaccination with the MMR II. Immunogenicity of the 3 production lots of MMR-RIT was consistent; more than 97% of the children had a seroresponse to MMR components. The coadministered vaccines elicited similar immunoresponses in the MMR-RIT and MMR II groups. Both MMR vaccines resulted in comparable reactogenicity profiles, and no safety concerns were detected.

Conclusions: If licensed, the MMR-RIT could provide a valid option for the prevention of measles, mumps, and rubella in children in the United States and would reduce potential risks of a vaccine shortage.

Keywords: vaccine; immunogenicity; safety.

Publication types

  • Clinical Trial, Phase III
  • Equivalence Trial
  • Multicenter Study
  • Randomized Controlled Trial

MeSH terms

  • Antibodies, Viral
  • Enzyme-Linked Immunosorbent Assay
  • Exanthema / etiology
  • Female
  • Fever / etiology
  • Government Regulation
  • Humans
  • Infant
  • Male
  • Measles / immunology
  • Measles / prevention & control
  • Measles-Mumps-Rubella Vaccine / administration & dosage
  • Measles-Mumps-Rubella Vaccine / adverse effects
  • Measles-Mumps-Rubella Vaccine / immunology*
  • Mumps / immunology
  • Mumps / prevention & control
  • Rubella / immunology
  • Rubella / prevention & control
  • Single-Blind Method
  • United States
  • Vaccination


  • Antibodies, Viral
  • Measles-Mumps-Rubella Vaccine

Associated data